As one of the main traditional food crops inhabited by the Qingjiang crane, rice has attracted the attention of growers in various "seedbed" fungal diseases during its growth and development.
Among them, the phenomenon of "rotten seedlings" and "dead seedlings" of rice seedlings in the seedbed has caused serious impact and damage to the yield and quality of rice seedlings, and reduced the quality of seedlings.
Picture 01~02): Rice seedlings have suffered from insect infestation
In this issue, Qingjiang Crane will focus on and chat with all the teachers about the related topics of "seedling seedling" seedbed diseases in the rice sowing season, aiming to elaborate on the symptoms, conditions and countermeasures of rice seedlings "rotten seedlings" and "dead seedlings", so as to provide a valuable reference for high-quality, high-yield and efficient cultivation of agricultural production. I hope it will be helpful to you, welcome to forward the circle of friends to share, and actively participate in the interactive comments.
There are 9 symptoms of "rotten seedlings" and "dead seedlings" of rice seedbed seedlings:
The "rotten seedlings" of rice seedlings are mainly manifested as black and rotten roots, yellowing and wilting leaves, and the whole seedling dies in severe cases. "Dead seedlings" refers to the sudden cessation of growth during the growth process, the leaves gradually wither, and finally the whole plant dies. These two "categories" will have a great impact on the growth of rice, resulting in a decrease in seedling yield and quality.
Picture 03~04): Prevention and control of root shrinkage of rice seedlings
According to the situation of "rotten seedlings" and "dead seedlings" over the years, Qingjiang Crane divides these symptoms into 9 conditions to share below:
01) "rotten seeds" appear on the seedbed:
That is, the seeds we sow, have not germinated or have just germinated and have "mold" and "spoilage" and cannot germinate or have a small germination rate. The color of the seed chaff often changes to "dark dark" until it is dark brown.
02）发芽的秧苗“翻根倒芽”：
It often occurs in varieties that are accustomed to traditional seedling "water seedlings". It is also found on dry-fed seedlings, but it is not too severe.
It often appears as a seed that sprouts after sowing, and the bud sheath is elongated but does not sink into the soil. Sometimes transversely or inverted, "top-heavy" feel feet, and the seed buds are bent downward or obliquely towards the seedling plate surface.
Picture 05~06): Robust and developed rice seedlings
03) Seedlings "black roots and rotten buds":
After the seed germinates, the seed root gradually rots from the root tip, does not grow new roots, the seed bud withers yellow or turns black, and there is a foul smell in the near future.
04) Seedlings suffer from "cotton rot" and rot buds:
It mainly occurs in "paddy field seedlings" and "plate seedlings", which are fungal diseases on traditional seedlings.
After sowing seeds, flocculent mycelial white mold grows at the crack of the chaff at the base of the bud, and sometimes soil particles adhere to the mycelium. The soil water layer contains iron oxide or algae matter, and sometimes it is earthy, brown or dirty green.
Picture 07~08): Rice seedlings raised in dry land
05) The seedlings unearthed in the seedbed show the symptoms of "white seedlings":
Seedlings grown and developed on the seedbed sometimes have "whole plant" "whole leaf whitening", and sometimes "local" leaf whitening. Local leaf bleaching is often "elongated" albino. In general, seedlings with albino leaves will basically die at the 3-leaf stage. However, the seedlings with local bleaching can be corrected when the conditions such as fertilization and spraying or temperature change, and they can still resume normal growth and development.
06) "knotty white" appears on the seedling leaves on the seedbed:
"Jiejiebai" seedlings, usually known as "flower seedlings", are mainly manifested in the leaves of unearthed rice seedlings, and there is a phenomenon of white and green.
Picture 09~10): Root disease of rice seedlings
07) The seedlings on the seedbed appear "shrunken and dead seedlings":
The unearthed seedlings are squeezed, the growth is backward, the plants are short, the leaves are less, the growth is weak, and the root system is less white and yellow.
08) The seedlings on the seedbed appear "peeling and dying":
"Peeling and dying" is also known as "yellow wilting and dead seedlings" for short, that is, the unearthed seedlings are gradually withered and dyed from the foot leaves to the heart leaves, from the leaf tip to the leaf base during the period of 1 leaf, 1 heart to 3 leaves, and the seedlings are pulled by hand, and the base is easy to break off.
09) The unearthed seedlings appear "dead heart" or "dead leaves" on the seedbed:
During the period of 2 to 3 leaves, it begins to roll up from the heart leaf and is stained green, and then spreads to the whole plant, causing wilting and death. Pull the seedlings by hand, and keep the base away. This is the difference from the "peeling and death" of seedlings. "Dead heart" or "dead leaves", in some places it is also called "green withered death".
Picture 11~12): Rice seedlings suffer from bacterial wilt and blight
Exploration of the causes of "rotten seedlings" and "dead seedlings" of rice seedbed seedlings:
01) "rotten seedlings" and "dead seedlings" caused by improper water management of seedling seedbeds:
The seedbed is too wet or too much water accumulates, resulting in a lack of oxygen in the roots and seedling rot. At the same time, insufficient water will also lead to the stunting of seedling growth and the phenomenon of dead seedlings.
For example, the emergence of symptoms such as "green wilting and death" of seedlings and "turning over roots and sprouts" of seedlings is due to the problem of "water".
02) "rotten seedlings" and "dead seedlings" caused by improper application of seedling fertilizer for seedling raising:
Excessive fertilization or unreasonable fertilizer ratio will lead to high soil salinity, burn the roots of seedlings, and cause rotten seedlings and dead seedlings.
For example, the appearance of symptoms such as "rotten seeds" of seedlings and "black roots and rotten buds" of seedlings is due to the problem of "fertilizer".
Picture 13~14): Rice seedlings bred by traditional methods
03) The seedlings are infected by pathogenic bacteria, causing "rotten seedlings" and "dead seedlings":
The presence of pathogenic bacteria in the soil, such as blight, cotton rot, etc., will directly lead to seedling rot and dead seedlings.
There are also seedlings unearthed at the seedling stage, such as "rotten seeds", "turning roots and sprouts", etc., which are related to the infection of fungal pathogens.
04) The temperature is not suitable during the growth and development of seedlings, resulting in "rotten seedlings" and "dead seedlings":
Low or high temperatures can adversely affect the growth of seedlings, resulting in slow growth or death of seedlings.
In addition, the "rotten seeds", "albino seedlings", "seedlings are white (flower seedlings)", "peeling and dead (yellow wilted seedlings)", and "green plants are dead (rolling leaves dead or withered hearts)" are all diseases that occur due to low temperature and can not meet the temperature requirements of rice seedlings in the seedling stage.
Picture 15~16): Integrated control of diseases and insects at the seedling stage of rice seedlings
05) Rice seedlings "rotten seedlings" and "dead seedlings" are related to over-sowing of seeds:
For example, when the seedlings on the seedbed appear "shrunken and dead", it is related to the seeds being sown too densely. Of course, "yellow wilted dead trees" and "green wilted dead" are also indirectly related to the over-sowing of seeds.
06) Seedlings "rotten seedlings" and "dead seedlings" are related to the "genetic disease" of seeds:
For example, when rice seedlings have "whole leaf bleaching", it may be related to the genetic disease of the seed.
07) The appearance of "rotten seedlings" and "dead seedlings" in seedbed seedlings is related to the use of herbicides:
Improper use of herbicides for seedbed soil closed weeding leads to "dead seedlings" in seedlings. The main manifestations are "over-concentration" of herbicides, or repeated use of herbicides.
Picture 17~18): Robust rice seedlings
08) The appearance of "rotten seedlings" and "dead seedlings" in seedbed seedlings is related to insect pests:
It is mainly related to the damage of seedlings and seedlings by underground pests such as soil silkworms, ground tigers, needleworms, mole crickets, etc. As a result, the root system cannot absorb water and nutrients from the soil, and the tree will wither and die.
09) Other causes caused by "rotten seedlings" and "dead seedlings" of seedlings:
For example, the seeds are not transparent to the sun, and improper seed storage damages the germination power of the seeds. When the seeds are soaked, the seeds are not soaked thoroughly or the water is not changed frequently, so that the seed grains lose their seed vitality before germination. During the germination process, accidents such as "burning buds" and "stickiness" occurred, which damaged the vitality of the seeds.
Or when the seeds are turned over, the chaff is damaged (panicle seeds), the rice grains are exposed, and the germs are infected without germination. The mud in the seedling field is too rotten, and the seeds are submerged in the mud and suffocated by lack of oxygen, and the seedlings cannot emerge. Alkaline fertilizers such as fertilizer that has not been fully decomposed or plant ash that has not been rained have been applied to the nursery bed have caused "fertilizer damage".
Picture 19~20): Intensive seedling raising of rice
Comprehensive prevention and control strategies for "rotten seedlings" and "dead seedlings" of rice seedlings:
01) Reasonable management of water in rice seedbeds:
Keep the seedbed properly hydrated and avoid being too wet or too dry (without removing the shed). In case of rainy weather (long period of rainy weather), it is necessary to drain the water in time to prevent water accumulation.
02) Reasonable fertilization, scientific fertilization, fully supply all kinds of nutrients needed for the growth and development of seedbed seedlings:
According to the soil fertility and seedling growth, the fertilizer should be reasonably prepared, so that the organic fertilizer can fully rot and there will be no "fertilizer damage". Do not apply alkaline fertilizers and avoid over-fertilizing or applying the wrong fertilizer. At the same time, it is necessary to pay attention to the application of organic fertilizer to improve soil structure.
Picture 21~22): Hydroponics and dry breeding of rice seedlings
03) Timely and accurate prevention and control of various diseases in seedling seedbeds:
Strengthen soil disinfection to reduce the breeding of pathogenic bacteria. When pests and diseases are found to harm seedlings and plants (when local diseases or central diseases occur), chemical control or biological control measures should be taken in time to control the expansion and spread of diseases.
Under normal circumstances, you can use 20 ml/bucket of water (500~800 times liquid) with 3% methyl lycin chloramphenicol water solution and 800~1000 times of 80% allicin chloramphenicol emulsifiable concentrate, and "rotten roots and dead seedlings" multi-functional foliar fertilizer multi-functional compound can be treated with stems and leaves.
04) According to the change of temperature in early spring, choose the opportunity to adjust the temperature and humidity in the shed in a timely manner:
Before sowing and during the growth process, it is necessary to pay attention to the temperature change at all times, and take timely measures to adjust the temperature of the shed to ensure the growth and development of seedlings under suitable temperature conditions.
Picture 23~24): Raising seedlings in a water seedling field
Words written at the end:
"Rotten seedlings" and "dead seedlings" of rice seedlings are important factors affecting the yield and quality of rice seedlings.
In order to effectively prevent and solve this seedling confusion problem, we need to have an in-depth understanding of its symptoms, occurrence conditions, and adopt corresponding coping strategies.
Through measures such as rational water management, scientific fertilization, pest control and temperature regulation, we can create a good environment for the growth of rice seedlings and improve the yield and quality of rice.
Picture 25~26): Vegetative growth and development period of seedling plants
At the same time, agricultural producers should also strengthen learning and exchanges, and continue to accumulate experience and knowledge, so as to better deal with the problems of "rotten seedlings" and "dead seedlings" of rice seedlings.
The government and all sectors of society should also pay more attention to technical training support to provide necessary guarantees and technical services for agricultural production. Only in this way can we ensure the stable development of rice production and make greater contributions to national food security and agricultural development.